This module in turn was based on the work (including an implementation of the algorithm in C) by Geoffrey Sampson, Department of Informatics, University of Sussex.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to

This Perl module implements the Simple Good Turing (SGT) algorithm for smoothing of probabilistic values developed by William Gale and Geoffrey Sampson.

The algorithm is described in detail in Sampson's Empirical Linguistics (Continuum International, London and New York, 2001), chapter 7. An online version of this paper is available at Geoffrey Sampson's homepage under http://www.grsampson.net/AGtf.html.